The embodiments described herein relate generally to a shutter device for a switchgear housing, and more particularly, to methods and devices used to prevent access to voltage line terminals within the switchgear housing by an overlap protective shutter device.
In known construction of a switchgear housing of the draw-out type, the movable electrical contacts of a circuit breaker are mounted within insulating bushings. The insulating bushings extend into insulating tubes which are mounted in terminal apertures of the associated switchgear housing to engage fixed electrical contacts disposed in the insulating tubes. In order to protect operating and maintenance personnel who enter the switchgear housing, known shutters are used to close the openings to the insulating tubes when the circuit breaker is removed from the normal operating position.
Conventional shutters are activated by the circuit breaker moving into and out of the switchgear housing. As the circuit breaker moves into the housing, known shutters move to a position either above or below the fixed electrical contacts to expose the fixed electrical contacts. As the circuit breaker moves out of the housing to disconnect from the switchgear, known shutters move to prevent access to the electrical contacts of switchgear. Conventional shutters, however, are not sized for multi-tiered, compact switchgear configurations.